Emergency fuel feeding system for airplanes



Feb. 20, 1962 w. M. HOYT EMERGENCY FUEL FEEDING SYSTEM FOR AIRPLANES Filed July 13, 1959 United States Patent 3,022,053 ER'IERGENCY FUEL FEEDING SYSTEM FOR AIRPLANES William M. Hoyt, Stanley, Iowa Filed July 13, 1959, Ser. No. 829,178 1 Claim. (Cl. 261--18) This invention relates to a system of emergency fuel feeding and combustible charge forming for use in connection with the internal combustion engines of airplanes, particularly, those of the smaller types, such as described in my forfeited application for patent, Serial Number 456,093, filed September 15, 1954, and allowed March 29, 1956.

It is the principal object of the invention to provide a system of the stated character, so constructed and operable as to advantageously and beneficially supplement the primary fuel feeding and carburetion instrumentalities of an airplane engine whereby, in the event of failure of the latter for any reason, as for example, because of fuel line clogging or similar fuel flow stoppage, breakage or improper functioning of the or any of the components thereof, carburetor icing or unforeseen exhaustion of fuel supply, a main fuel tank and regular carburetor by-passing emergency supply of combustible fuel to the engine may be immediately and positively effected for maintaining its continued operation; the invention, therefore, affording important factors of safety to the end of attaining and sustaining eficient flight of an equipped airplane.

It is also an important object of the invention to provide novel and positively operable means communicating with the engine intake manifold, beyond its carburetor, so operable that fuel sprayed into said means will be therein admixed with properly proportioned amounts of air and constitute a highly combustible charge for introduction into the engine manifold and delivery into the engine cylinders for firing.

Another object of the invention is to provide an emergency fuel supply device operable in a manner which ensures delivery of gaseous charge to an equipped engine in the event of unforeseen failure of its main fuel feeding system, and which will give the engine its normal fluid requirements during and throughout usual or unusual flight attitudes of the airplane powered thereby, including such abnormalcies as inverted flight.

The foregoing, as well as other objects, advantages and mer torious teachings of my invention, will be in part obv1ous and in part pointed out in the following detailed disclosure thereof, when taken in conjunction with the accompanying drawings, it being understood that the forms of the invention presented herein are precise and what are now considered to be the best modes of embodying its principles, but that modifications and changes may be made in specific embodiments without departing from its essential features.

In the drawings:

FIGURE 1 is a semi-schematic view of the invention operatively connected to an airplane engine intake manifold, parts of the installation being shown in elevation,

and others in section.

FIGURE 2 is an enlarged detail of the fuel spray nozzle operatively mounted in the emergency air'and fuel intake and admixture chamber (shownin section) which, in turn, is connected to and communicates with the regular engine intake manifold beyond its point of connection with the regular engine charge forming device or carburetor; also, showing the air intake modulating and the fuel passage control valves of the invention and the manner in which they are interconnected for collective operation, and

FIGURE 3 is an enlarged detail in vertical section of the emergency fuel tank (a part being broken away) and 3,922,653 Patented Feb. 20, 1%52 the fuel intake device therein by means of which constant flow of fuel from said tank will be maintained regardless of flight attitude of the equipped airplane.

Referring in detail to the drawings, I have shown my invention operatively installed in a conventional type of airplane engine fuel feeding system wherein there is included a main fuel tank 1, a carburetor 2 connected to the tank by a conduit 3 equipped with a fuel supply control and regulating valve 4 and a filter 5, and the engine intake manifold 6. The latter is fragmentally illustrated.

It is to be understood that the type of airplane engine fuel feeding system, such as above referred to, may be different, particularly, since my invention is adaptable to or installable in various other types of engine fuel feeding systems.

Generally, the invention includes an air intaking and charge admixing device 7, a carburetor shut-off valve 8, and an emergency fuel supply tank d.

The air intaking and admixing device consists of a conduit 10 of appropriate length, one end of which has an intake manifold engaging head 11 fixedly mounted thereon and communicating therewith. The normally upper and lower sides of the head are preferably flat and have ways formed therein communicating, via said head, with the conduit 10.

The head is positioned between the intake manifold 6 and the carburetor 2. Its flat upper side is flushly or flatly and fluid tightly connected with and contacted to a flattened intermediate and under side portion of the manifold with the opening or port therein communicating with a like way in the manifold, as shown and indicated at 12. Thus, communication is established between the conduit 19 and the manifold 6.

Fixedly mounted on the upper side of the carburetor 2 and communicating with its carbureted fuel discharge port or way is a slide valve casing 13 whose upper side has an opening or port therein.

The conduit carried head 11 is seated on and connected by suitable means to the valve casing upper side (see FIG- URE 1) with the Way in its lower side communicating with the fuel discharge port of the carburetor 2.

A plate valve 14 is slidably received within the casing 13 from an open end thereof and has a port 15 formed in the same. The shape and size of said port, preferably, substantially corresponds to that of the way in the lower side of the conduit head 11 and the carburetor fuel discharge port and is so positioned as to be selectively regulatable and communicable therewith. In consequence, it will be understood that intercommunication between the carburetor and the engine intake manifold 6 is controllable by the valve 14 and its adjustment in the casing 13; also, that the point of such intercomrnunication is effected beyond the carburetor discharge port.

To effect operation of the slide valve 14 in its casing, i.e., sliding to predetermined positions with relation to the upper side port thereof, a stem 16 is connected to one end of the same and extends through and beyond the closed end of the casing where it is connected to operating linkage, hereinafter more fully described.

If desired, the opposite end of the valve may be up turned or otherwise formed to provide a finger piece whereby to facilitate its engagement and manual sliding, if such be desired or required.

In order that a combustible charge may be formed if and when the emergency fuel system is activated, the conduit 10 has an intermediate portion thereof enlarged,

. as at 17, whereby to constitute an admixing chamber. A

spray nozzle 18, of construction and design as to supply the rated fuel quantity at the required pressure, is sub stantially centrally received within the admixing chambe' intermediately of its ends and directed toward the conduit head 11, being fixedly mounted therein by extending one side of the same through a suitable packing gland 19 in one side of said chamber to a point therebeyond. A feed pipe 20 is connected to this extended end of the nozzle and communicates with the emergency fuel supply tank, presently described. In use, the nozzle Will function to mix air and fuel at a rate and in proportion to vaporize the spray ensuing therefrom and effect and maintain efiicient operation of the equipped airplane engine. 7 V

It may here be noted that difierent types of nozzles can be used in lieu of the above described one and, of course, that they would vary according to the type of fuel and the size of the equipped engine.

The emergency fuel supply tank 9 is of suitable shape and size,.being received and supported at a suitable point within the airplane fuselage and provided with an appropriate filling opening normally closed by a cap 9.

Flow of fuel from the emergency fuel supply tank through the feed pipe 20 to the nozzle 18 is controlled and/or regulated by means of a rotatable valve 20 interposed in said feed pipe. By rotatable adjustment of said valve, fuel fiow through the feed pipe may be increased or decreased to the desired or required extent.

The feed pipe 29 extends through one end wall of and into the emergency fuel supply tank 9 and has its inner end equipped with a suitable form of coupling 21 to which one end of a flexible hose 22, or the like, is connected.

Connected to the remaining or free end of the hose 22, by means of a suitable form of coupling 23, is a weighted fuel intake head, generally indicated by the numeral 24. Said head consists, preferably, of a disklike body .of appropriate Weight, having foraminated upper and lower Walls 25. It will, of course, be understood that the aforesaid coupling 23 communicates with the interior of the fuel intake head 24 at a point between its foraminated walls 25. The fuel intake head being weighted and connected to the inner end of the fuel feed pipe 20 within the tank 9, it will be understood that said head will ensure an intaking of fuel into and through the fuel feed pipe 20 at all times, particularly, since the flexible hose 20 and said head will permit the latter to follow the fuel regardless of the attitude or the position of the aircraft. Consequently, a continuous and dependable fuel supply will be provided to the fuel feed pipe 20, and thence, to the nozzle 18, giving the equipped engine its normal fuel requirement, even in unusual fiight attitudes, such, for example, as inverted flight, etc.

To provide adequate or sufficient pressure 'to the fuel 26 within the tank 9 whereby to cause its outflowing therefrom through the intake head 24 and the feed pipe 20 to and from the spray nozzle 18, it is necessary that;

a suitable pressure head shall be effected and maintained, at a predetermined and required degree, Within said tank. To effect this, a pipe 27 is tapped into the upper side of the tank 9, as shown in FIGURES 1 and 3. A T-coupling 28 is interposed in said pipe, while a suitable form V of pressure relief valve 29 is also mounted. in the pipe beyond the coupling 28. A pressure creating and sup-- plying device,'such as a hand pump, etc., designated by the numeral 30, is connected to the free or remaining branch of the coupling 28 through a pipe 31. Thus,

with operation of the pump 30, a pneumatic head of the required degree of pressure may be effected within the fuel tank. If or when such pressure should exceed the required degree, the relief valve 29 will function to release such excess. 7

If desired, a suitable type of pressure. gauge, generally indicated by the numeral 32, may be tapped into the fuel feed pipe 20 in order that the degree of pressure within the emergency fuel feed tank 9 may be at all times accurately determined.

outwardly of or beyond the mixing chamber. By rotat-' ably adjusting the valve, a properly modulated inflow of air will be effected into and through the conduit open free end into said chamber for admixture with the nozzle sprayed fuel and the forming of a combustible charge.

It is recognized, and in some instances, it is preferable that the air intake into the conduit 10, as above described may be efiected from or through a suitably heated source. Such usage of hot air, as will be understood and appreciated, will be especially'advantageous in avoiding or preventing icing conditions; moreover, to improve the combustible quality of the emergency carbureted fuel dcliveredto the engine cylinder from the intake manifold 6, particularly, under or in the presence of certain climatic conditions.

Different forms of means may be satisfactorily employed for effecting operation of the plate valvei14, the valve 29' and the valve 33. I prefer, however, that such valves shall be collectively operable. To accomplish this, linkage, indicated by the numeral 34, is effected between the free end of the stem 16 and a suitably mounted bellcrank lever 35, whose free end has linkage 36 connected thereto. The linkage 36, in turn, is connected to the actuating levers 37 and 37' of the valves 20' and 33, respectively. It will thus be seen that motion imparted to either of the linkage 34 or 36 or to the bell-crank lever 35 will be transmitted to the valves connected thereto. In consequence, a collective operation of said valves will thereupon be effected, and so, the plate valve 14 would 1 be moved to a position closing communication between the carburetor 2 and the conduit head 11, while the valve 20 would be opened allowing fuel, under pressure, to flow through the feed pipe 20 to and from the spray nozzle 18, and the butterfly or gate valve 33 opened to permit of the intaking and passage of air through the free and open end of the conduit 10 into the admixing and charge forming chamber 17 of said conduit.

In, operation of the invention and assuming that an adequate supply of pressure is present in the emergency fuel storage tank9, it will be understood that the control valves 20 and 33 are'normally closed and that the slide valve 14'is in its open position, as shown in FIGURE 1 of the drawings, i.e., with the port 15 therein registering with the way in the lower side of the head 11 with the discharge of the carburetor 2.

' Upon failure of fuel supply to the intake manifold 6 from the carburetor 2, for reasons such as hereinbefore stated, or any thereof, the plane pilot collectively operates the linkage connected valves 14, 20 and 33, opening the fuel flow valve 29' in' the feed pipe 20 and the air flow valve 33in the conduit 10 beyond the admixing chamber 17. At such time, fuel will be flowed from the emergency fuel storage tank 9 through the intake head 24 and the fuel feed pipe 20 to the spray nozzle 18. Simultaneously, a flow of air will be effected through the conduitlt) carbureted charge will be delivered from the conduit 10 into the head 11, and since the valve 14 is in closed position, into the intake manifold 6'for delivery to the airplane engine cylinders whereby to maintain their operation.

Because the carburetor 2 has been positively disconnected from the intake manifold 6 due to theclosing of the slidable plate valve 14 at a point'beyond said carburetor discharge, it will be understood and appreciated that any combustible mixture whatsoever which might have remained in the carburetor will be prevented from being withdrawn therefrom through the head 11 into the engine intake manifold. Thereby, the combustible mixture delivered to said head for introduction into the intake manifold from the conduit 10 and its admixing chamber 17 will be in no manner aifectedand will not have its combustible qualities diminished.

The intake head 34, movably received in the emergency fuel storage tank 9, will function, at all times, to permit the flow of fuel into and from the same, this notwithstanding the attitude of flight of the equipped airplane, inasmuch as said intake head will, at all times, follow the tank contained fuel 26.

Should the pressure provided by the pump 30 within the storage tank 9 become excessive, possibly due to flight altitudes and/or other reasons, such excessive pressure will be released from the tank by the relief valve 29; moreover, fuel flow pressure through to feed pipe 20 may be readily determined by referring the the gauge 32.

When fuel supply requirements are returned to the regular fuel supplying system of the equipped engine, the valves 20 and 33 are closed and the slide valve 14 is opened through the aforedescribed linkage. Thus, the supply of combustible fuel from the admixing chamber 17 of the conduit 10 will be discontinued and flow of carbureted combustible charge from the carburetor 2 through its discharge into the head 11 and thence into the intake manifold 6 will be permitted.

I claim:

An emergency fuel supply for internal combustion engines, comprising in combination with an engine intake manifold and a carburetor communicable therewith, a conduit, an enlarged and chambered head on one end of the conduit communicating therewith, the remaining end of the conduit being open and valved, said head being removably interposed between the manifold and carburetor and having ports in its opposite sides communicable with said manifold and carburetor, a valve slidably mounted between one side of the head and the carburetor fuel discharge port controlling communication between the carburetor, head and manifold, an intermediate portion of said conduit being enlarged and forming a chamber therein, a spray nozzle in and discharging into the chamber toward the head, valved fuel supply means connected to the nozzle, and means operable to collectively and adjustably open the conduit valve and fuel supply valve and close said slidable valve.

References Cited in the file of this patent UNITED STATES PATENTS 1,257,089 Mason Feb. 19, 1918 1,272,898 Beldon July 16, 1918 1,398,315 Cawthra Nov. 29, 1921 1,871,055 Hasbrouck Aug. 9, 1932 2,595,720 Snyder May 6, 1952 

